The present invention relates to a bone anchoring nail. In particular, it relates to a bone anchoring nail having a shaft with a longitudinal bore and a plurality of openings in the wall of the shaft, and a head with a substantially U-shaped recess for accommodation of a rod. The bone anchoring nail can be used, for example, for anchoring a spinal rod in the pedicles of adjacent vertebrae for stabilizing the spinal column or it can be used in any other type of bone anchor application using a rod or a rod-shaped element.
A bone anchoring device in form of a bone screw comprising a screw head and a threaded shaft, wherein an axial bore is provided which is connected to the outside through a plurality of radial bores is known from WO 01/26568. Bone cement can be injected through the bone screw and into the bony tissue surrounding the threaded shaft. US 2004/0147929 A1 discloses a bone anchoring device having a tubular element having a section with a bone thread on its outer wall, a tip and a head which can be connected to the tubular element, wherein the head comprises a U-shaped recess for receiving a rod. The insertion of such a bone anchoring device is accomplished by screwing-in which is force and time consuming. Further, during screwing, forces act onto the bone which can be too large in certain situations, for example in the case of older and/or weak bones.
US 2004/0220575 A1 discloses a bone anchoring element for anchoring an external device in the bone. The bone anchoring element comprises a head which is connectable to the external device and a shaft connected to the head, wherein the shaft has a predetermined section with a bone thread and at least one bone thread-free section within said predetermined section. The bone anchoring device can be pushed into a predrilled hole in the bone and then turned so as to allow anchoring by means of the bone thread. The anchoring device can be unscrewed due to the presence of the bone thread. In a specific embodiment the shaft comprises a longitudinal bore with radial bores leading to the outside for the purpose of allowing the introduction of a medical agent or bone cement into the pre-drilled hole.
U.S. Pat. No. 5,743,912 and JP 09149906 A disclose medical implants comprising a shaft with a longitudinal bore and radial openings and a threaded section at one end.
US 2006/0089642 A1 describes an implant for vertebrae and other bones which is formed as an elongated cylindrical body with a series of perforations penetrating the cylinder wall and communicating with the cylinder bore. The bore may be filled with a bone growth mixture. The implant is not suitable for connection with a spinal stabilization rod.
For certain clinical requirements, in particular for the stabilization of weak osteoporotic bone, in pediatric surgery, in surgery of the cervical spine or in neurosurgery, there is a need for bone anchoring devices which can be connected to an external stabilization rod or rod-shaped element, wherein the bone anchoring devices can be inserted even more quickly and with lower insertion forces than the known devices while providing a safe fixation which is comparable to that of screws.